Trim the green beans by cutting the stems off then add to a large mixing bowl.
Drizzle over the olive oil and season with the garlic powder, salt and pepper.
Transfer the seasoned beans to the air fryer basket then air fry at 400°F/205°C for 7-9 minutes or until the beans are fork tender and starting to brown.
Remove and serve with a generous squeeze of lemon juice.
You could also grate over some fresh lemon zest or parmesan cheese right before serving.